Medical Reporting: Where Fact Meets Fiction

Media Sounding False Alarms on Health Risks

July 20, 2002
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LONDON, JULY 20, 2002 (Zenit.org).- Every week seems to bring new media reports about dangers to our health. In fact, many of the scare stories are superficial, if not downright wrong.

Take the announcement that Swedish scientists had discovered that acrylamide, a chemical substance present in french fries and potato chips, causes cancer. "Tests which confirm the existence of a possible cancer-causing chemical in much of the food we eat are causing worldwide concern," the British Guardian warned May 18. It told readers that British scientists had also detected "the potential carcinogen in cooked potatoes, crisps, breakfast cereals and rye crispbreads."

In the United States, the San Francisco Chronicle reported June 28 on the World Health Organization meeting convened in Geneva to discuss the problem. "The overriding thing the committee concluded is that, given that we know acrylamides are cancer-causing in animals and probably in humans, it is intolerable that they are in foods at the levels found, and we have to find a remedy," WHO spokesman Gregory Hartl said.

Steven Milloy didn't share those fears. Milloy, the author of the book "Junk Science Judo," published an article July 3 in the Washington Times that cast doubt on the WHO claim. Milloy noted some scientists seem to have induced the cancer in laboratory rats by feeding them astronomically high levels of acrylamide. And the rats used in the experiments were bred to be genetically disposed to cancer, he stated.

Moreover, the U.S. Environmental Protection Agency has already studied acrylamide, in order to regulate its levels in drinking water. EPA research found that, for a 154-pound human to have a significant increase in cancer risk (similar to the rats), he would have to eat 486 large servings of french fries weighing out at 182 pounds, every day, for life.

Tricks with numbers

Then came the warning on the dangers of hormone replacement therapy for women. "In a move that may affect millions of women, U.S. government scientists Tuesday stopped a major study of hormone replacement therapy on the risks and benefits of combined estrogen and progestin in healthy menopausal women, citing an increased risk of invasive breast cancer," CNN reported July 9.

However, the London Daily Telegraph's science correspondent, Robert Matthews, pointed out July 14 that the HRT case is "a scientific scandal involving tricks with numbers that would make Enron's accountants blush."

Matthews reported comments made on a BBC radio program by professor David Purdie of the University of Hull. The important thing to keep in mind, explained Purdie, is that although the U.S. study was halted due to a 26% increased risk of breast cancer among those on the therapy, the overall risk of breast cancer is very low. "Thus women taking the HRT face a cancer risk that is just 26% more than a very small number -- which is still a very small number," he said.

In fact, the trial showed that there would be 8 more deaths per year among 10,000 women taking this form of HRT, as compared with the same number of women who didn't.

Media interpretation of statistics was also defective in the reports a few months ago concerning alcohol use by teen-agers in the United States. In February the National Center on Addiction and Substance Abuse published a study claiming that a quarter of all alcohol sold in America is consumed by teen-agers.

But, as Michael Kinsley pointed out March 1 in the Washington Post, after the initial reports came out the New York Times observed that the study was wrong because it "had not applied the standard statistical techniques in deriving that number."

The error was due to the fact that 40% of the survey sample was teen-agers, even though they comprise less than 20% of the general population. Correcting for this mistake produces an 11% share of total alcohol consumption by teens. The Associated Press, CNN and others passed along the 25% figure, however, without their reporters looking at how the survey was structured, Kinsley commented.

Big fat lies

Another news topic is the health danger of obesity. No doubt there are real problems in this area, but not to the extent that some claim. The Washington Times noted June 20 that many reports allege that fat kills 300,000 Americans per year, making it the nation's second leading cause of premature death.

A database search reveals that this "fact" has been repeated in more than 1,000 news stories over the past three years alone, noted the newspaper. However, the supposed source for this claim was a 1993 medical study that in fact attributed the premature deaths to sedentary lifestyle and poor dietary habits -- not to weight. So says University of Virginia professor Glen Gaesser in the forthcoming revised edition of his book "Big Fat Lies," the Washington Times said.

Indeed, the authors of the 1993 study, Michael McGinnis and William Foege, became so frustrated by the chronic misinterpretation of their data that in 1998 they published a letter in the New England Journal of Medicine objecting to the misuse of their study.

More accusations of playing fast and loose with the truth came as a result of a BBC drama on genetically modified crops. "Ludicrous and inflammatory lies," decried Mark Tester, a Cambridge University biologist, the London Times reported May 31.

The program, "Fields of Gold," is a two-part thriller that -- according to Tester -- has a plot strewn with "ridiculous errors of fact" that poison the debate about GM food. The drama tells the story of a GM-created superbug that kills elderly people and wildlife.

Lord May of Oxford, the president of the Royal Society, condemned it as a "ludicrous piece of alarmist science fiction" that portrays the technology in hysterically inaccurate fashion, reported the Times.

Not only does the program assume that genes can leap indiscriminately from species to species, but it also shows a scientist creating GM crops in a food blender, and obtaining rare antibiotic resistance genes from regular hospital waste.

"The way that a TV film about GM crops can assume such importance and provoke such controversy is a sign of our fearful times," the Times noted June 3. "These days we find it harder to know where to draw the line between fantasy horrors and real-life risks."

Matters are even worse on the Web. Consumers searching for health information on the Internet are likely to find sites selling products or making baseless claims, Reuters reported July 16.

A team of researchers made an Internet search using five portals: Yahoo, America Online, Microsoft Network, Lycos and Go. They searched for eight terms related to heart disease, eight related to cancer and eight related to weight loss. The analysis included the first 10 sites listed by the five portals for the different topics, for a total of 1,200 Web sites. They reported on their results in a letter published in the July 17 issue of the Journal of the American Medical Association.

Only 35% of the sites were non-promotional and based on scientific information. About 11% of the sites were based on medical evidence but sold products, and 22% of the sites were not based on scientific research and sold products. Nearly one-third of the sites were personal pages, book catalog sites or unavailable sites.

"Numbers don't lie," says the adage. But, to paraphrase another, "Not all numbers are equal." Which is something readers would do well to remember in reports on science and medicine.